Revision as of 04:23, 19 May 2016 by LubOlimex (talk | contribs) (How to change HDMI, VGA and LCD resolutions under Debian?)

A13-SOM-1.jpeg A13-SOM-2.jpeg

A13-SOM-XXX features:

  • A13 Cortex-A8 CPU and Mali 400 GPU
  • 256 or 512MB DDR3 RAM memory
  • Power supply managment
  • 1x LCD connector
  • 3x GPIO connectors
  • MicroSD card connector
  • DEBUG-UART connector for console debug with USB-SERIAL-CABLE-F
  • status LED
  • Power LED
  • RESET button
  • 3.3V input power supply
  • PCB dimensions: 61 x 33 mm

Official Images from OLIMEX



Torrent of Debian release 1: A13-SOM-256 Debian Linux with kernel 3.4.90+

Direct download location of Debian release 1: A13-SOM-256 Debian 4GB SD-card image release-1 with hardware accelerated video and more


Please note that the RAM memory of A13-SOM-512 was recently changed and there are two different Debian images: one for boards with the memory we previously placed HYNIX H5TQ2G83CFR, and another image for the memory placed now - SAMSUNG K4B2G0846Q.

Newest official Debian releases (recommended):

Torrent of Debian release 3 preliminary - suitable for boards with SAMSUNG K4B2G0846Q DDR3 RAM memory: A13-SOM-512 Debian Linux with kernel 3.4.90+ in case of problems test with the previous release 2.

Torrent of Debian release 2 - suitable for boards with SAMSUNG K4B2G0846Q DDR3 RAM memory: A13-SOM-512 Debian Linux with kernel 3.4.90+, suitable for boards with SAMSUNG DDR3 RAM

Torrent of Debian release 1 - suitable for boards with HYNIX H5TQ2G83CFR DDR3 RAM memory: : A13-SOM-512 Debian Linux with kernel 3.4.90+, suitable for boards with HYNIX DDR3 RAM

Direct download location of Debian release 1 - HYNIX H5TQ2G83CFR: A13-SOM-512 Debian 4GB SD-card image release-1 with hardware accelerated video and more

The image features:

  • Linux Kernel 3.4.90+
  • LXDE desktop environment
  • Mplayer CLI
  • GCC 4.6
  • 4.3"(480x272), 7"(800x480), 10" (1024x600) and 15.6" (1366x768) LCD and touchscreen support
  • GPIO
  • I2C
  • USB WIFI RTL8188CU, Ethernet AX88772B
  • dpkg
  • git
  • i2c-tools
  • perl
  • xorg
  • Python 2.7
  • MOD-WIFI-RTL8188
  • A13-LCD 4.3″TS 4.3″ LCD with backlight and touchscreen 480×272 pixels
  • A13-LCD7″TS 7″ LCD with backlight and touchscreen 800×480 pixels
  • A10-LCD10″TS 10.1″ LCD with backlight and touchscreen 1024×600 pixels
  • Micro SD card
  • I2C2(100KHz)
  • I2C1(100KHz)
  • Default Login: root/olimex

Tested board peripherals with this image:

  • GPIO - located at /sys/class/gpio
  • LCD - supported are A13-LCD4.3TS, A13-LCD7TS, A13-LCD10TS
  • Touch screen - you need calibrate LCD before using touch screen. Type: ts_calibrate and then test it with ts_test
  • RTL8188CU - MOD-WIFI-RTL8188
  • USB_OTG - works as OTG device and Low/Full/High USB host
  • USB_HOST - works as Low/Full/High USB host
  • mico_SD_card - allow Linux boot
  • I2C2(100KHz) - /dev/i2c-2
  • I2C1(100KHz) - /dev/i2c-1

Note: the A13-SOM-Debian-SD card which we have in our web store contains the same image on 4GB Class10 fast micro SDcard, if you want to use this image please use card of Class10 speed or the performance of Linux will be very slow.

Note: in the previous Debian releases the Ethernet was auto-detected and initialized during boot BUT this was causing big delays in the start-up of the board if you didn't want to use Ethernet or if there wasn't Ethernet cable connected.

You can enable it by following these two steps:

1. To check under what name the LAN is associated write "ifconfig –a"

2. If, for example, it is under eth0 name, then write: "dhclient eth0"

This should enable the Ethernet and then SSH would also be available.


Note that the Android is suitable only for the A13-SOM-512 version of the board (the 256 version of the board is not equipped with enough RAM to run Android smoothly). To upload the Android to the NAND you would also need A13-SOM-WIFI-4GB (to extend the board with NAND flash memory).

Torrent of Android 4.2.2 release 1 for NAND memory with 720p HDMI and 800x480 (7 inch display) video support: A13-SOM-512 Android for NAND with HDMI and 7 inch display support

Torrent of Android 4.2.2 release 1 for NAND memory with 720p HDMI and 1024x600 (10 inch display) video support: A13-SOM-512 Android for NAND with HDMI and 10 inch display support

Direct download of Android 4.2.2 release 1 NAND memory with 720p HDMI and 800x480 video support: A13-SOM-512 Android for NAND

The image is with these features:

  • Android 4.2.2
  • NAND image will work only on A13-SOM-512+A13-SOM-WIFI-4GB
  • MicroSD card image will work on A13-SOM-512+A13-SOM-WIFI and A13-SOM-512+A13-SOM-WIFI-4GB
  • Different images support 7" LCD 800x480 pixels and 10" LCD 1024x600 pixels
  • Touchscreen supported
  • GPIO support
  • USB-Ethernet ASIX 88772
  • USB-WIFI RTL8188
  • USB-OTG support USB device and USB host with Low/Full/High speed
  • USB-HOST-top Low/Full/High speed
  • micro SD card
  • I2C1
  • I2C2
  • Buttons


A13 Datasheet

A13 datasheet

A13 User Manual

A13 Users manual


Power supply and consumption

If used as a stand-alone board A13-SOM can be powered from:

  • +3.3V power source, applied to GPIO-1 connector

Typical power consumption is as follows:

  • A13-SOM-512 + A13-SOM-WIFI-4GB running Debian - consumption: 0.45A @ 5V
  • A13-SOM-512 + A13-SOM-WIFI-4GB + A13-LCD7-TS running Debian - consumption: 0.75A @ 5V
  • A13-SOM-512 + A13-SOM-WIFI-4GB + A13-LCD7-TS running Android - consumption: 0.40A @ 5V

Additionally, if used together with A13-SOM-WIFI the whole setup can be powered from:

  • +5V via miniUSB cable, applied to USB_OTG connector
  • +5V power source, applied to the +5V pin near the red PWR_LED

Board dimensions

A13-SOM-XXX basic dimensions might be seen in the picture here: A13-SOM board dimensions


A13-SOM-256/512 schemaitc is available at GitHub

A13-SOM-WIFI schematic and CAD files are at GitHub

The CAD product used to design A13-SOM-WIFI is Eagle and you can download evaluation free version from their web-site.

Board Layout



Linux Commands

Linux-Commands Brief Linux Command reference


The Debian Linux Python package for A13-SOM is called pyA13SOM. It is installed in the default Debian image. More information and examples on how it can be used might be found here:

Link to pyA13SOM package at python.org

GPIO under Debian Linux

The GPIOs are defined in the script.bin of the Debian distribution. If you edit the script.bin you can change the names of the GPIOs. You can also remove the definitions for certain pins or add additional ones that we might have missed.

Inside the Debian Linux the GPIOs are located in /sys/class/gpio directory. Before using a GPIO you would need to export it.

There is an easy way to export all GPIOs:

 mount -t debugfs none /sys/kernel/debug
 for i in `seq 1 1 230`; do echo $i > /sys/class/gpio/export; done

To list all available GPIOs write:

 cat /sys/kernel/debug/gpio

This would return:

 gpio-1   (sysfs               ) in  hi
 gpio-2   (sysfs               ) in  hi
 gpio-3   (sysfs               ) out hi
 gpio-4   (sysfs               ) in  lo
 gpio-5   (sysfs               ) in  lo
 gpio-6   (sysfs               ) in  lo
 gpio-7   (sysfs               ) in  lo
 gpio-8   (sysfs               ) in  lo
 gpio-9   (sysfs               ) in  lo
 gpio-10  (sysfs               ) in  hi
 gpio-11  (sysfs               ) in  lo
 gpio-12  (sysfs               ) in  lo
 gpio-13  (sysfs               ) in  hi
 gpio-14  (sysfs               ) in  lo

The rest of the GPIOs have to be defined in the fex. Refer to this wiki article: how to edit board configurations and definitions

An example for a single port add is below (PB03):

   root@A13:~# echo 1 > /sys/class/gpio/export

to make PB03 output

   root@A13:~# echo out > /sys/class/gpio/gpio1_pb3/direction

to make PB03 high level(3.3V)

   root@A13:~# echo 1 > /sys/class/gpio/gpio1_pb3/value

to make PB03 low level(0V)

   root@A13:~# echo 0 > /sys/class/gpio/gpio1_pb3/value

note that:

There might be multiplexing on some of the pins especially if you are using a shield! Consider that when picking a GPIO. Refer to the schematics of the board and the shield for clearer view of the possible multiplexing locations.

How To?

How to generate boot-able SD-card Debian Linux image for A13-SOM?

The building instructions for the latest images might be found in this wiki article: building Debian for A13-SOM-256 and A13-SOM-512 (with support for XYNIX or SAMSUNG RAM memory)

Wordpress post on the building the previous (now outdated) Debian image (suitable only for boards with HYNIX memories, does not work properly with boards with SAMSUNG memories): wordpress post

How do I write the Linux image to a micro SD card to use with my A13-SOM board?

To write a Linux image to an SD card under Windows we use Win32 Disk Imager):

  • Download Win32 Disk Imager Win32 Disk Imager
  • Insert card
  • Start program
  • Select file
  • Click "write"

To write a Linux image to an SD card under Linux:

For instance you have an image with the file name of "debian_2g.img". It would be downloaded to the SD card connected to a Linux machine using one of the following commands:

  • # dd bs=4M oflag=sync if=debian_2g.img of=/dev/sdX


  • # cp debian_2g.img /dev/sdX

where X is the uSD card.

How to change HDMI, VGA and LCD resolutions under Debian?

The default SD card setup is made with settings for 7 inch LCD 800x480.

If you want to change to video output to other LCD (or in rare cases VGA) resolution under Debian then you have to start change_display.sh script file in /root directory.

For Linux Debian you would need to execute a shell script to be able to change the resolution. It is very good idea to use a serial cable for connection to the board from a personal computer since in this case you are dependent on a video resolution (a cable like USB-SERIAL-CABLE-F). If you want to change to some other LCD, VGA or HDMI resolution then you have to start change_display.sh script file in /root directory. When you are logged as super user in the board type:

  For Debian Wheezy releases: ./change_display* (* = press 'tab' to auto-complete)
  For Debian Jessie releases: change_display* (* = press 'tab' to auto-complete)

and press "Enter".

Note that the script should be executed as super user. Under the command line interface you are automatically logged as super user (user "root", password "olimex"). However, under the graphical environment you are not auto-logged as super user and you must type "sudo" before the command (in the GUI the super-user is "olimex" and the password is "olimex")

Choose the resolution and the interface (LCD or VGA). Note that VGA output is hard to implement and requires both additional hardware and good soldering experience. The supported resolutions are:

For LCD:

  1. 4.3" (480×272)
  2. 7" (800×480)
  3. 10" (1024×600)

For VGA (A13-SOM lacks VGA support on hardware level):

  1. 1680×1050
  2. 1440×900
  3. 1360×768
  4. 1280×1024
  5. 1024×768
  6. 800×600
  7. 640×480
  8. 1920×1080
  9. 1280×720

How to edit board configurations and definitions in the official Debian Linux?

There is a separate article on the subject here: editing the script.bin configurations

How to properly calibrate a display under Debian

If the problem is under Debian Linux make sure you are properly logged in the LXDE interface! Else applying calibration would not happen for the current user - if you are calibrating from the X graphical interface make sure that you are logged as user “olimex” (if calibrating without the X, the user is “root”).

  #su olimex

enter the olimex password:olimex

   #sudo ts_calibrate

calibrate the touch screen and reboot the board

   #sudo reboot

It would be a good idea to test with Android or another Debian image also, it has a built-in calibration application by default.

How to control PWM under Linux?

There is an article here: how to add pwm

How to correctly power off OLinuXino running from NAND Flash

In this blog post we explain what are the problems of sudden power down. This is common problem for all computers running an OS made specifically for handheld devices. Here you can read more about MLC NAND Flash and Linux file system.

How to restore the Android image on NAND Flash

Android corruption might happen if the A13-SOM-512 and A13-SOM-WIFI setup loses suddenly all power supply. In that case you can restore the Android image. Download an Android image from above (there are two images available one for 7 inch display and the other for 10 inch display), then follow the algorithm:

1. Install and run LiveSuit software (can be found here: [1]).

2. Go to “SelectImg” tab of the program and point to a valid Android image (the latest official one may also be downloaded above).

3. Disconnect the power supply and USB cable from the A13 board.

4. Press and hold HOME button, apply power supply 5V, release HOME button.

5. Connect USB cable to the mini USB connector.

6. You will be asked for drivers for the bootloader. Navigate to the folder where you extracted the LiveSuit and install the drivers from the respective executable (or manually point the installer to the drivers folder in the LiveSuit’s installation path).

7. LiveSuit will detect the board and would ask for the method of writing the image. Choose method of writing the image and confirm your wish to write the image.

8. Wait till upgrade succeeds

How to add STK1160 video capture driver support in Kernel 3.4

STK1160 driver backport by Dimitar Tomov